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Check out The Fuel Pulse Show Podcast

Check out The Fuel Pulse Show Podcast

Check out The Fuel Pulse Show Podcast

Check out The Fuel Pulse Show Podcast

Check out The Fuel Pulse Show Podcast

Check out The Fuel Pulse Show Podcast

Check out The Fuel Pulse Show Podcast

Check out The Fuel Pulse Show Podcast

Check out The Fuel Pulse Show Podcast
Check out The Fuel Pulse Show Podcast

4 min read

Algae in Diesel? Algae belongs in the sea!

Algae in Diesel? Algae belongs in the sea!

As the years since the implementation of ultra-low sulfur diesel for all onroad diesel fuels stretch out, more and more professionals are learning what fuel handling personnel have known for years - the likelihood of having the problem of microbes and algae in diesel fuel is classified as a matter of 'when', not 'if'.  They're also learning that finding a real solution to solve this problem is easier said than done.

The first thing to clear up is that, while we called the problem 'algae', it's not actually algae.  Algae is what the average joe calls diesel fuel microbes, probably because they're easy to visualize. But algae is a microscopic plant, and since plants need light to grow, there's no algae in diesel fuel.  What there are is bacteria and fungus that grow and thrive in stored fuels that have even a little bit of water in them. Those are the microbes that cause all the problems.

A bigger problem than it used to be.

We kicked this blog off making an inference that fuel microbes are a growing problem, and there's a reason we did that. Ultra-low sulfur diesel fuel ("ULSD") behaves differently when it's stored than the higher sulfur diesel fuels of years past. ULSD is better for the environment because most of the sulfur has been taken out at the refinery (and thus can't go into the air and cause acid rain). But the unforeseen consequence of that is that there's now nothing left in the fuel to inhibit or prevent the growth of hungry microbes looking for places to grow and thrive.  Microbes don't like sulfur - it keeps them away. So back before 2006, all you had to do in most cases to keep any stored diesel free of microbes was to keep water buildup under control. That's not the case any more, and many of the old-standard solutions that used to work for keeping microbes and algae away just don't cut it.  It's not their fault. They're water-controllers for fuel, not biocides.

We said the magic word. Biocide.

We know better than anyone that the diesel fuel additive industry is, shall we say, "competitive".  Every joker and their brother seems to be coming up with magic solutions to dump in fuel and fix every fuel problem known or imagined.  

But when you're talking about infected fuel tanks, it's nothing to play around with.  The consequences for users in terms of time and money are huge and expensive.  And nobody has time to waste on snake oil garbage that claims to do things like "controls microbial growth" when it doesn't do a thing about that.

The only thing that works to kill and get rid of microbes and "algae" in stored fuel is a biocide. A pesticide for fuel. You can have fuel treatments that make fuzzy claims about "controlling water to help prevent or control bacterial growth in fuel". But what they're really saying is

"This is the kind of stuff that used to work in high sulfur diesel fuels. And if you keep water buildup out, you might keep microbes from growing. But with ULSD fuels being so easy to attract bacteria, there's no guarantees. Meanwhile, we've got your money, so if you have a problem despite using this, better luck next time."  

Hardly a satisfying claim if they were really honest.

There's not that many true biocides on the market, and for good reason. We called them "pesticides for fuel" because they're poisonous and hazardous. But that's the kind of chemical you need to kill microbial living organisms in the fuel.

Because there are few real biocides available, maybe it's a good idea to point out what you need to look for and what separates an honest-to-goodness biocide that's going to kill your microbe problem and make it go away, vs. a non-biocide water controller or other fuel additive that just making fuzzy claims in their marketingto try and fool consumers into parting with their money thinking they're getting a real solution to a serious fuel microbe problem they may have.

Have to be registered, both with the EPA and in each individual state

Real biocides have to be registered and approved by two different entities - the EPA's Office of Pesticides and by each individual state they're sold in.  These processes are expensive and time consuming, both to start and to keep up with.  These state and national authorities require this so they can make sure the public's safety is protected and they know what's out there.  Some fly-by-night company trying to make a quick buck will not have gone through these registrations. So as a consumer, it should make you wonder about how good their "biocide" product really is.

Have to be properly labeled with the risks detailed

This, too, is to protect the public's safety.  Biocides are strong and hazardous, and anyone applying them needs to know everything about the risks. Therefore, the labels for real biocides tend to have lots of "fine print" on them to detail all the potential risks and what to do about them.  They may even be "accordian" labels with multiple pages that unfold. If you go to Home Depot or Lowes, grab and bottle of Roundup and look at the back label. You'll see what we're talking about.

A product that isn't a "real biocide" will probably have just a few lines or a paragraph on the label with generic risk phrases on them.  Keep out of reach of children. Don't drink this stuff. Not enough to satisfy the legal requirements. And that shouldn't be enough for a potential user to feel at ease about how safe or effective it is.

And the Registration Numbers, too

They're also required to have two specific numbers on their label - the EPA Registration Number and the Fulfillment Number.  The Registration Number helps the authorities trace the origin of the biocide quickly if there's a problem.  Like if someone dumps a drum of biocide into a lake and the local authorities have to know, quickly, what they're really dealing with.  The Fulfillment Number helps trace where it was packaged. Again, in case there's an emergency problem.

"Non-biocides" aren't going to list these numbers. Even though any product claiming to kill microbes in fuel MUST have them. They won't, because they're skirting the law.  Which should be another red flag for consumers.

Don't Play Games - Stick With What Works

For fuel handlers and companies and large-scale users who have stored fuel tanks, they're all going to be faced with infected fuel eventually. Not if, but when. When that happens to you, remembering these guidelines should increase your chances of finding a truly effective solution that will solve your problem and help you get back to work.

You may be interested in these other posts about diesel fuel:

Four Essentials to Know About Fuel

Low Sulphur Diesel Problems: Corrosion in Storage and Dispensing

Low Sulphur Diesel Problems: Corrosion in Storage and Dispensing

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Recognizing Diesel Fuel Algae

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